path: root/arch/arm/mm/proc-v7.S

/*
 *  linux/arch/arm/mm/proc-v7.S
 *
 *  Copyright (C) 2001 Deep Blue Solutions Ltd.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 2 as
 * published by the Free Software Foundation.
 *
 *  This is the "shell" of the ARMv7 processor support.
 */
#include <linux/init.h>
#include <linux/linkage.h>
#include <asm/assembler.h>
#include <asm/asm-offsets.h>
#include <asm/hwcap.h>
#include <asm/pgtable-hwdef.h>
#include <asm/pgtable.h>

#include "proc-macros.S"

#define TTB_S		(1 << 1)
#define TTB_RGN_NC	(0 << 3)
#define TTB_RGN_OC_WBWA	(1 << 3)
#define TTB_RGN_OC_WT	(2 << 3)
#define TTB_RGN_OC_WB	(3 << 3)
#define TTB_NOS		(1 << 5)
#define TTB_IRGN_NC	((0 << 0) | (0 << 6))
#define TTB_IRGN_WBWA	((0 << 0) | (1 << 6))
#define TTB_IRGN_WT	((1 << 0) | (0 << 6))
#define TTB_IRGN_WB	((1 << 0) | (1 << 6))

/* PTWs cacheable, inner WB not shareable, outer WB not shareable */
#define TTB_FLAGS_UP	TTB_IRGN_WB|TTB_RGN_OC_WB
#define PMD_FLAGS_UP	PMD_SECT_WB

/* PTWs cacheable, inner WBWA shareable, outer WBWA not shareable */
#define TTB_FLAGS_SMP	TTB_IRGN_WBWA|TTB_S|TTB_NOS|TTB_RGN_OC_WBWA
#define PMD_FLAGS_SMP	PMD_SECT_WBWA|PMD_SECT_S

ENTRY(cpu_v7_proc_init)
	mov	pc, lr
ENDPROC(cpu_v7_proc_init)

ENTRY(cpu_v7_proc_fin)
	mrc	p15, 0, r0, c1, c0, 0		@ ctrl register
	bic	r0, r0, #0x1000			@ ...i............
	bic	r0, r0, #0x0006			@ .............ca.
	mcr	p15, 0, r0, c1, c0, 0		@ disable caches
	mov	pc, lr
ENDPROC(cpu_v7_proc_fin)

/*
 *	cpu_v7_reset(loc)
 *
 *	Perform a soft reset of the system.  Put the CPU into the
 *	same state as it would be if it had been reset, and branch
 *	to what would be the reset vector.
 *
 *	- loc   - location to jump to for soft reset
 */
	.align	5
ENTRY(cpu_v7_reset)
	mov	pc, r0
ENDPROC(cpu_v7_reset)

/*
 *	cpu_v7_do_idle()
 *
 *	Idle the processor (eg, wait for interrupt).
 *
 *	IRQs are already disabled.
 */
ENTRY(cpu_v7_do_idle)
	dsb					@ WFI may enter a low-power mode
	wfi
	mov	pc, lr
ENDPROC(cpu_v7_do_idle)

ENTRY(cpu_v7_dcache_clean_area)
#ifndef TLB_CAN_READ_FROM_L1_CACHE
	dcache_line_size r2, r3
1:	mcr	p15, 0, r0, c7, c10, 1		@ clean D entry
	add	r0, r0, r2
	subs	r1, r1, r2
	bhi	1b
	dsb
#endif
	mov	pc, lr
ENDPROC(cpu_v7_dcache_clean_area)

/*
 *	cpu_v7_switch_mm(pgd_phys, tsk)
 *
 *	Set the translation table base pointer to be pgd_phys
 *
 *	- pgd_phys - physical address of new TTB
 *
 *	It is assumed that:
 *	- we are not using split page tables
 */
ENTRY(cpu_v7_switch_mm)
#ifdef CONFIG_MMU
	mov	r2, #0
	ldr	r1, [r1, #MM_CONTEXT_ID]	@ get mm->context.id
	ALT_SMP(orr	r0, r0, #TTB_FLAGS_SMP)
	ALT_UP(orr	r0, r0, #TTB_FLAGS_UP)
#ifdef CONFIG_ARM_ERRATA_430973
	mcr	p15, 0, r2, c7, c5, 6		@ flush BTAC/BTB
#endif
	mcr	p15, 0, r2, c13, c0, 1		@ set reserved context ID
	isb
1:	mcr	p15, 0, r0, c2, c0, 0		@ set TTB 0
	isb
	mcr	p15, 0, r1, c13, c0, 1		@ set context ID
	isb
#endif
	mov	pc, lr
ENDPROC(cpu_v7_switch_mm)

/*
 *	cpu_v7_set_pte_ext(ptep, pte)
 *
 *	Set a level 2 translation table entry.
 *
 *	- ptep  - pointer to level 2 translation table entry
 *		  (hardware version is stored at -1024 bytes)
 *	- pte   - PTE value to store
 *	- ext	- value for extended PTE bits
 */
ENTRY(cpu_v7_set_pte_ext)
#ifdef CONFIG_MMU
 ARM(	str	r1, [r0], #-2048	)	@ linux version
 THUMB(	str	r1, [r0]		)	@ linux version
 THUMB(	sub	r0, r0, #2048		)

	bic	r3, r1, #0x000003f0
	bic	r3, r3, #PTE_TYPE_MASK
	orr	r3, r3, r2
	orr	r3, r3, #PTE_EXT_AP0 | 2

	tst	r1, #1 << 4
	orrne	r3, r3, #PTE_EXT_TEX(1)

	tst	r1, #L_PTE_WRITE
	tstne	r1, #L_PTE_DIRTY
	orreq	r3, r3, #PTE_EXT_APX

	tst	r1, #L_PTE_USER
	orrne	r3, r3, #PTE_EXT_AP1
	tstne	r3, #PTE_EXT_APX
	bicne	r3, r3, #PTE_EXT_APX | PTE_EXT_AP0

	tst	r1, #L_PTE_EXEC
	orreq	r3, r3, #PTE_EXT_XN

	tst	r1, #L_PTE_YOUNG
	tstne	r1, #L_PTE_PRESENT
	moveq	r3, #0

	str	r3, [r0]
	mcr	p15, 0, r0, c7, c10, 1		@ flush_pte
#endif
	mov	pc, lr
ENDPROC(cpu_v7_set_pte_ext)

cpu_v7_name:
	.ascii	"ARMv7 Processor"
	.align

	__CPUINIT

/*
 *	__v7_setup
 *
 *	Initialise TLB, Caches, and MMU state ready to switch the MMU
 *	on.  Return in r0 the new CP15 C1 control register setting.
 *
 *	We automatically detect if we have a Harvard cache, and use the
 *	Harvard cache control instructions insead of the unified cache
 *	control instructions.
 *
 *	This should be able to cover all ARMv7 cores.
 *
 *	It is assumed that:
 *	- cache type register is implemented
 */
__v7_ca9mp_setup:
#ifdef CONFIG_SMP
	ALT_SMP(mrc	p15, 0, r0, c1, c0, 1)
	ALT_UP(mov	r0, #(1 << 6))		@ fake it for UP
	tst	r0, #(1 << 6)			@ SMP/nAMP mode enabled?
	orreq	r0, r0, #(1 << 6) | (1 << 0)	@ Enable SMP/nAMP mode and
	mcreq	p15, 0, r0, c1, c0, 1		@ TLB ops broadcasting
#endif
__v7_setup:
	adr	r12, __v7_setup_stack		@ the local stack
	stmia	r12, {r0-r5, r7, r9, r11, lr}
	bl	v7_flush_dcache_all
	ldmia	r12, {r0-r5, r7, r9, r11, lr}

	mrc	p15, 0, r0, c0, c0, 0		@ read main ID register
	and	r10, r0, #0xff000000		@ ARM?
	teq	r10, #0x41000000
	bne	3f
	and	r5, r0, #0x00f00000		@ variant
	and	r6, r0, #0x0000000f		@ revision
	orr	r6, r6, r5, lsr #20-4		@ combine variant and revision
	ubfx	r0, r0,